This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Recently published (Nov 2005) appropriateness criteria for single photon emisson computed tomography myocardial perfusion inmaging (SPECT MPI) is the first cardiology-specific document that identified whether or not a test is appropriate based on clinical indications [1]. A total of 52 clinical scenarios were rated: 27 as appropriate (A), 13 as uncertain (U), and 12 as inappropriate (I). Using these criteria, we developed a simplified clinical appropriateness score, and applied it prospectively to investigate findings of SPECT MPI and outcome in a large patient cohort from our institution.